Segment for motion-picture shutters.



E. w; CLARK. SEGMENT FOR'MOTION PICTURE 'SHUTTERSF APPLICATION min FEB. 23. 1915. RENEWED DEC. 1.191s.

- Patented J uiy 10, 1917.

' UNITED STATES PATENT OFFICE.

EDWIN W. CLARK, OF KANSAS GITY, MISSOURI, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, T PHOTOMOTION COMPANY, OF KANSKS CITY, MISSOURI. A COR- 1,233,186. Application filed February 23, 1915, Serial No. 9,964. Renewed December 1, 1916.

PORATION OF MISSOURI.

SEGMEIYT FOR MOTION-PICTURE SHUTTERS.

State of Missouri, have invented certain new and useful Improvements in Segments for Motion-Picture Shutters; and I do declare the following to be a full, clear, and

exact description of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference beinghad to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

My invention relates to a llght obstructing segment for the shutter of a motion picture projector, and has for its principal object toprovide means whereby the marked contrast between the illumination of a screen during the period of exposure of a film when the latter is stationary, and the total absence of illumination during the moving period may be reduced or eliminated, and thereby enhance the appearance of the projected picture and reduce the strain incident to viewing pictures projected by an apparatus utilizing a shutter having opaque sections. Y

It is a well known fact that in projecting pictures from a film onto a screen the film is moved intermittently so that the projection is made while the film is stationary, and that when the film is advanced an opaque portion of the shutter is interposed between the film and lens to completely block the picture during the moving period. This ordinary method, therefore, produces alternate periods of projection and blank so that the contrast is that between white and black on the screen. As the periods usually occur more rapidly than sixteen per second the. shutter disturbance is hardly visible to of a shutter of mesh composition and of a plurality of plies, wherein the mesh of each ply is of such fineness that the strands are of greater thickness than the spaces therebetweenand arrange the plies at oppo- Specification of Letters Patent.

Patented July 10, 1917'.

Serial No. 134,228.

site sides of the shutter at an angle to each other and at other than a right-angle to the rays of light, in order that while light may be deflected by the strands of the first ply and diffused through the openings in the succeeding ply, the lines of a picture are prevented from reaching the screen without completely darkening the screen as the shut- I ter segment passes across the projected rays.

In the drawings wherein my invention is illustrated in its preferred form,

Figure I is a perspective view of part of a projector equipped witha shutter containing my improvements.

Fig. II is an elevationof' the shutterproper.

Fig. III is a cross section of the shutter particularly illustrating the arrangement of fabric in a two-ply shutter.

Fig. IV is a similar view of a reversed form of shutter segment.

Referring more in detail to the drawings:

1 designates the projector case. 2 the lens, 3 a film'and 4 a shutter shaft, which parts are constructed and arran ed in the ordi nary manner so that the siutter shaft may be driven by the usual mechanism (not shown). a

The shutterproper comprises a hub 6, which is fixed on the shaft at and has radial ribs 7 which carry a peripheral ring 8' to form a shutter frame.

Mounted on the rim 8 and attached to ments 10 of translucent mesh material, here shown to be, and preferably consisting of fabric such as silk or the like, wherein the threads are closely woven in order to form relatively small interstices.

In the preferred arrangement of the shutter the peripheral ring 8 and clamp 9 are of different width so that the plies of the shutter segment extend at an angle to each other from the clamp to the ring, so that rays of light striking strands in the firtt ply are deflected through the interstices of said ply and will impinge against the threads of the next ply in a line that will prevent their passing directly through the interstices of the succeeding ply and be thereby modified in intensity when deflected through the interstices of the latter ply.

v7 bile I have mentioned but a single ment, it is apparent that'more may be used, as it is customary for shutters to comprise a plurality of segments in order to interrupt the projection a plurality of times during each revolution of the shutter. 1 In using aprojector equipped with my improved shutter,the turning is arranged in the ordinary manner.

With a shutter of the construction herein described, when the shutter segment is in- I terposed between the glower and the lens,

the light is not entirely eliminated, as rays striking the first ply of the se ent pass through the interstices and are 1 eflected by the strands so that the rays are diffused between the plies; the light passing'through theinterstices being stopped or diffused by the strands in the succeding ply so that the rays are deflected and diflused before reaching the opposite side of the shutter and very materially softened without being entirely lost, thereby eliminating the marked contrast between the white and black. periods 'of' the ordinary'projection.

While light may be difi'used through the shutter, as described, the lines of the picture i being projected, when diffused by the strands thereby-obviates a marked contrast between 'of the separate plies, are completely lost in the shutter so that no projection of the picture is made on the screen, so that the use of the shutter results in a partial projection of light with no projection of picture and the'periodsof projection and blank without causing confusion by a partial projec- 2. A shutter segment comprising a plu rality of plies of foraminous material with the plies arranged at an angle to each other and at other than a right angle to the rays of light, whereby light rays passing through the film during periods of movement also pass through the-shutter segment and are diverted by the segment whereby. diiius'ed light but no picture reaches a screen.

I 3. The combination in a projector,-of a shutter comprising a plurality of plies each arranged at other than a right angle'to the other and to a direct path from the pro- I jector to a screen, whereby light rays are diverted through the shutter to throw a diffused light on a screen during periods of film movement.

In testimony whereof I afix my signature in presence of two witnesses.

EDWIN w. CLARK.

Witnesses:

LYNN A. RoBmsoN, LETA E. CoA'rs. 

